The present invention relates to a fitting for a fluidic device.
In liquid chromatography, a fluidic analyte may be pumped through a column comprising a material which is capable of separating different components of the fluidic analyte. Such a material, so-called beads which may comprise silica gel, may be filled into a column tube which may be connected to other elements (like a control unit, containers including sample and/or buffers). During operation, such columns may be subjected to high pressures of, for instance, up to 600 bar and more.
Fittings for coupling different components, such as separation columns and conduits, of fluidic devices are commercially available and are offered, for instance, by the company Swagelok (see for instance http://www.swagelok.com).
A known fitting element is configured to provide a fluidic coupling to a fluidic device, and comprises a capillary and an inlay located in a cavity of a front side of the capillary. The inlay protrudes over the front side, at least before coupling of the capillary to the fluidic device. Upon coupling of the capillary to the fluidic device, the front side is fitted to the fluidic device for connecting a fluid path of the capillary to a fluid path of the fluidic device, and the inlay provides a sealing of the fluid path of the capillary and the fluidic device.
A known fitting assembly comprises a nut, a ferrule, and a ferrule tip that may be assembled by an operator. The fitting assembly includes a nut with first and second ends, with the second end configured to receive the first end of a ferrule, and a ferrule tip with a first end having an externally tapered portion configured to abut the second end of the ferrule and a second end configured to be received in a component or fitting of a liquid chromatography system. The nut, ferrule and ferrule tip of the fitting assembly have passageways therethrough for receiving and removably holding tubing.
Another known fitting includes an elongated cylindrical body with a conical ferrule secured to its forward end, and with the body and ferrule having aligned through bores sized to allow a capillary tube to be passed through them. The elongated body has medially located external helical threads, and a knurled nut is rotatably coupled to these threads. The body also has elongated axially directed gripping fingers with inwardly facing gripping regions thereon normally spaced from but suited to be biased radially against the capillary tube in the fitting bores. A tubular gripping nut is threaded onto the external body threads, suited to be axially shifted along the body upon relative nut/body rotation. The nut and body have cooperating cam surfaces suited to engage upon relative nut/body rotation and bias the finger gripping regions tightly against the capillary tube for securely retaining tube as positioned within the fitting.
However, the requirements regarding sealing performance and mechanical stability of a fitting of fluidic measurement devices further increases with further increasing operation pressure values.
What is needed, therefore, is a fitting for a fluidic device that overcomes at least the shortcomings of known apparatuses described above.